The present invention relates generally to multiphase flow metering, and more specifically, to the use of patch antennas in the metering of multiphase compositions.
In process industries, oil and gas industries and other such areas, it is often necessary to accurately measure the composition and flow rate of material flowing inside a pipeline. In cases where the electrical conductivity of the medium is very low, for instance wet-gas flows, where the composition has a small percentage of oil and/or water, and the change in dielectric constant with fractional changes in oil/water is very small, it becomes difficult to measure changes in composition.
Commercially available sensors for measuring fluids in the petroleum industry are based on a variety of principles (either a single technique or a combination of several techniques). For example, impedance sensors, capacitive and/or inductive sensors, dual-energy gamma sensors, venturi meters, and microwave sensors (attenuation/phase/resonance) have all been used. Currently, there are numerous microwave-based flow metering sensors available offering varying degrees of sensitivity, complexity and costs. Typically, measurement of amplitude and phase of the signals is used to reconstruct various flow regimes, such as slug, churn, and annular. With all the methodologies of measuring multiphase flow, accuracy, sensitivity, cost and technical complexity is a concern.
Accordingly, there is an ongoing need for improving upon multiphase flow metering.